Bobbin



Dec. 21, 1965 G, G, HENDRY, JR 3,224,696

BOBBIN Filed NOV. 29. 1963 INVENTOR.

Bg/@fm 6. Hendry, Jr

Homey Unted States Patent O 3,224,696 BGBHiN Glenn G. Hendry, .'fr., Fiber Industries, incorporated, Shelby, N.C. aired Nov. 29, 1963, sa. No. sans@ ll Ciaim. (Cl. 242-463) This invention relates to a unique, disposable bobbin particularly adapted as a shipping core for synthetic yarn. More particularly, the invention is directed to a disposable paper bobbin utilized for winding light continuous filament synthetic yarn having a denier below about 35 and can be used in a draw-twisting operation of said light filament synthetic yarn wherein the yarn is directly wound on the bobbin eliminating a rewinding or back-winding operation.

The most desirable bobbin used for purposes of winding filaments or fibers for shipment to the user which can be utilized is one which combines greater strength with lightness, contains a surface which will not catch the yarn or fiber, is made by an inexpensive procedure utilizing inexpensive materials so as to be disposable, among other known advantages. In the winding and unwinding of synthetic yarns, especially of low denier, it is of particular significance that the upper portion of the bobbin contain a smooth edge, such as a plastic coverall, to avoid snagging of the filaments. Additionally, in view of the internal stresses of the synthetic fiber while relaxing on the wound bobbin, metal, plastic or other expensive inserts are adhered to the bobbin to provide added support. The use of plastics and metals among other expensive materials to produce the bobbin increase costs so that the bobbins so produced are required to be returned by the user after the fibers or filaments have been used.

It is the object of this invention to provide a unique, simple, inexpensive and disposable paper bobbin for use in the winding of synthetic yarn of low denier.

The bobbin of this invention is made of two distinct and separate parts; namely, a thin-walled outer paper tubular member having its upper end formed into an inturned annular edge portion and a removable inner reinforcing paper tube. The uniqueness of the bobbin is related to the fact that the two separate parts of the bobbin are not physically adhered to each other, such as using an adhesive or a glue. These separate parts of the paper bobbin are fashioned into a tubular form either cylindricalv or conical in such a manner that the two separate parts will significantly fit into one another; i.e., the inner walls of the thin-walled outer tubular member will make intimate contact throughout its length with the outer wall of the inner reinforcing tube while the upper portion of the inner reinforcing tube will merely abut the lower inner edge of the inturned annular edge portion of the outer paper tube. However, the proportions of the separate parts of the bobbin are such that the inner reinforcing tube can be readily removed when there is no synthetic yarn or thread wound on the thin-walled outer member.

The significant feature of the empty bobbin of this invention relates to the fact that the turning of the bobbin depends on frictional force between the inner wall of the outer tubular member and the outer wall of the inner reinforcing tube as well as a moving force between the inner wall of the reinforcing tube and the movable means of the rotatable spindle. T-he use of paper, such as kraft paper, in the production of the separate parts of this bobbin without the use of adhesives between these parts, permits the frictional force between the walls to move the entire empty bobbin assembly with a minimum of slippage in the initial Winding of the synthetic yarn. After the initial synthetic yarn, such as nylon, polyester, polypropylene, and the like of low denier is wound on the outer paper tubular member, the inherent shrinkage of this synthetic yarn will slightly compress the outer ICC paper tubular member against the inner reinforcing paper tube to provide a gripping effect between the separate members; and, at this point, the turning of these separate parts of the bobbin no longer depends on frictional force. After the synthetic yarn has been wound on the bobbin assembly, the inner reinforcing tube cannot be physically removed without destroying the bobbin assembly until the liber or filaments are removed from the bobbin.

Although the cost of the paper bobbin of this invention is minimal in regard to metal, plastic, etc. reinforcement bobbins, an added feature of the bobbin of this invention is readily apparent since after the filament or fiber wound on the bobbin has been removed and used, the inner reinforcing tube can be easily removed from the bobbin assembly and, if desired, returned for further use in another bobbin assembly of this type to provide added savings to the fiber or filament manufacturer.

The bobbin of this invention can be more fully understood by reference to the accompanying drawing representing an embodiment of the invention in which:

FIGURE 1 is a side view of the bobbin partly shown in section, and FIGURE 2 is a sectional view along the lines 2--2 of FIGURE 1 demonstrating a rimmed portion broken away.

Referring to FIGURES 1 and 2, a thin-walled outer paper tube 11 containing an inturned inner edge portion lf3 is fitted over a removable inner reinforcing paper tube 12. The inner reinforcing paper tube 12 abuts the lower edge 14 of the inturned annular edge portion 13 but is not connected in any manner. The central opening 15 permits the spindle to pass through this opening. The wall 16 of the thin-walled outer paper tube l1 is in intimate contact of the wall 17 of the removable inner reinforcing paper tube 12 but is also not connected in any manner.

The separate laminated paper tube sections of the bobbin of this invention can be formed by convolutely winding a paper sheet by known procedures. The character of the paper from which the tube sections are made can vary widely. It is preferred, however, to use kraft paper and it is essential that the surface of the tube sections and especially the surface of the thin-walled outer paper tubular member be substantially smooth to avoid snagging of the low denier filament yarn. The walls of the thinwalled outer paper tubular member should be strong enough to maintain its tubular shape and should exceed 0.05 inch in Width, preferably in excess of 0.1 inch width. It is essential that the thin-walled outer paper tubular member contain a smooth inturned annular edge portion or shoulder formed by crimping the top end of said outer paper tubular member. It would be appreciated that in unwinding a package of thread from a bobbin such as described, the filament or fiber yarn is continually removed by being drawn axially from the bobbin and it is essential that t-he end of the bobbin past which the thread moves as it is being unwound should be smooth so as not to catch the yarn and cause breakage. The removable inner reinforcing paper tube must be of sufficient strength to support the package of yarn throughout the bobbin length. The width of the wall of the reinforcing tube should be thick enough so that the total width of the wall of the thinwalled outer paper tubular member plus the width of the reinforcing tube should at least be about 0.2 inch in width with a preferable width in excess of 0.30 inch, depending on the size of the total package of filament to be wound on the bobbin.

To illustrate the bobbin of this invention, a t-hin-walled outer kraft paper tubular member having a 0.1 inch wall width and containing a 0.38 inch width mold end at the top was placed over an inner reinforcing kraft paper tube having a 0.25 inch wall width. A polyester filament of 20 denier was directly wound on the bobbin from a drawtwisting operation to produce a two-pound package. The yarn package produced was satisfactory in the prevention of slippage of the inner winding of the packaging and at the same time avoided fraying and breakage of the low denier yarn as it was placed on and withdrawn axially from the bobbin.

It is understood that the foregoing description is merely illustrative of preferred embodiments of the invention of which many variations may be made by those skilled in the art within the scope of the following claim without departing from the spirit thereof.

What is claimed is:

A disposable bobbin utilized for winding light continuous filament synthetic yarn having a denier below about 35, comprising a thin walled outer paper tubular member having its upper end containing an inturned annular edge portion and a removable inner reinforcing paper tube free of connections with said member other than frictional force, said tube having such length and outer proportions so as to make intimate contact with the inner wall of the said outer paper tube and having such inner proportions so as to make intimate contact with the movable means of a rotatable spindle, said intimate contact of the inner wall of said removable inner reinforcing paper tube with said spindle suicient so as to turn said paper tube on the turning of said spindle and during said turning utilizing a minimum of frictional force on the outer wall of said removable inner reinforcing paper tube to turn said outer tubular member for purposes of winding synthetic yarn on said disposable bobbin.

References Cited by the Examiner UNITED STATES PATENTS MERVIN STEIN, Primary Examiner. 

